Jamie Spears -- Good Riddance, Sam Lutfi!!!

Britney Spears' father Jamie is THRILLED after beating Brit's ex-manager Sam Lutfi in court -- but tells TMZ, the victory is bittersweet.

We just spoke to Jamie on the phone, and he tells us, he's pleased the judge tossed out Sam's defamation lawsuit against the Spears family -- before it went to jury -- but he expressed disappointment at not being able to take the stand and tell the "real" story.

Jamie says it was painful to relive the darkest days of Britney's life -- when he thought Britney might actually die -- but no one took it harder than Brit's mom Lynne.

Jamie says Britney hasn't spoken to Lutfi in four or five years.

As we reported, an L.A. judge dismissed Lutfi's lawsuit against the Spears family yesterday for lack of evidence -- a lawsuit in which Lutfi claimed the Spears family defamed him, physically attacked him, and breached a management contract he had with Britney.

As for Britney's conservatorship -- Jamie says he DOES foresee an end, but he's not sure when exactly.